Field of the Invention
The present invention relates to a display method and a display apparatus.
Description of the Related Art
Liquid crystal displays and plasma displays have been used as display apparatuses for displaying images and characters. These display apparatuses do not have the function of diopter adjustment.
In recent aging societies, there are many people who suffer from presbyopia. Hence, there is a demand for display apparatuses that allow diopter adjustment, in particular flat panel displays (which will also be referred to as “FPD” hereinafter) that allow diopter adjustment.
For the sake of explanation, a case with presbyopia will be described by way of example. With proliferation of cellular phones and digital cameras, people view FPDs outdoors in many occasions. It is very troublesome for a person to put on reading glasses, or farsighted glasses every time he or she views an FPD of a mobile device such as a cellular phone or a digital camera and to take off them after that.
In the case of cellular phones, people view the FPD when sending or reading mails or playing video games on the cellular phones.
FPDs are also used in digital single lens reflex cameras as live view monitors. When using a digital single lens reflex camera, it is not practical to put on reading glasses to view the live view monitor and to take off them to view a distant object. Moreover, there are many occasions that require a user to view the monitor to use the graphical user interface (GUI) on the monitor to change setting such as the shooting mode.
In the case of car navigation systems, a user is typically driving a car when viewing the monitor. Therefore, it is unsafe to put on reading glasses to view the monitor from front and to take off them after that. It is practically impossible to put on reading glasses and take off them in such an occasion.
Moreover, in the case of liquid crystal displays of personal computers, it is troublesome for a user to put on reading glasses to view the monitor screen. Hence, there is a demand for electronic devices that allow a user to view the monitor without the need to put on reading glasses.
For example, WO2013/118328 discloses a display apparatus that displays a virtual image using a lens array and a display device in combination.
Douglas Lanman and David Luebke ‘Near-Eye Light Field Displays’ discloses a near-eye light field displays.